are you guys using impact for axle nut or hand torquing with torque wrench to spec?

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got a new hub/wheel bearing assembly installed at a shop recently and i saw them use the air impact to get the axle nut back on. they tightened the lugs with the torque wrench but the axle/spindle nut only got the air impact.

i have heard some people say that its crucial to get the axle nut torque spot on as over tightening it can cause early wheel bearing failure

what do you guys think of this? how do u guys tighten the axle nut?

and for the one that the shop installed, should i loosen it and retighten by hand and use torque wrench or leave it how it is now?

thx
 
No air.
Only torque wrench.
They have a torque spec.
Mine was very high, higher than mine, I had to borrow one.
 
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Some/most of the nuts are one time use so theoretically once they've been tightened they shouldn't be reused, some have a little flange that you tap into a groove on the axle to lock them. Just something to consider. Personally I prefer to torque them correctly, but I've banged a few on with the impact on 'max' and called it good with no issues. Really its your call.
 
I used to just slam them on with the air gun, all the way until they wouldn’t spin anymore. Never had a problem, but for the last 10 years or so I’ve been torquing them to spec.
 
Hear me out on this. What about cars where they have a castellated nut and cotter pin where the tightening ritual says (paraphrased) "Tighten to XXX and then tighten further to line up a hole" Seems to me there is a minimum spec on those but a much higher maximum as 1/8th of a turn could really be quite a bit much more. Probably why the one use nuts were invented, good bit more repeatable on the torque if you're not having to line something up.
 
The few times I had to remove and then to replace axle nuts , I used a 3/4" break over bar & long cheater pipe to remove and replace them . No problem . Had to stand on the pipe to break them loose . So , I stood on the pipe to " torque " them .
 
got a new hub/wheel bearing assembly installed at a shop recently and i saw them use the air impact to get the axle nut back on. they tightened the lugs with the torque wrench but the axle/spindle nut only got the air impact.

i have heard some people say that its crucial to get the axle nut torque spot on as over tightening it can cause early wheel bearing failure

what do you guys think of this? how do u guys tighten the axle nut?

and for the one that the shop installed, should i loosen it and retighten by hand and use torque wrench or leave it how it is now?

thx

Didn't you just ask this question in another thread?

 
I've only replaced one cv axle assembly in my life (knock on wood). I thought that the axle nut only held together the sealed bearing/knuckle/axle assembly. How does the axle nut affect the bearing load?
 
I've only replaced one cv axle assembly in my life (knock on wood). I thought that the axle nut only held together the sealed bearing/knuckle/axle assembly. How does the axle nut affect the bearing load?

Maybe it depends on what type of bearing you are using, the older non sealed type that sits inside a race inside the rotor I could see how this is affected by the nut torque,the newer sealed hubs I don't think it will have any.....
 
If you look at your stress-strain curves for metal, you'll see that metal moves under load. Bearings are designed for maximum life within microns of clearance. The wrong torque will give the wrong clearance in the bearing.
 
I've heard that proper torque sets the bearing preload. I've only had to replace one wheel bearing and I made sure to torque it correctly. The spec is there for a reason.
i would say that what you heard is correct, i'm sure that it sets the bearing preload. your bearing will last much longer if you follow this process. i also seem to remember that some vehicle maybe chrysler could have a severe issue with the outer cv joint if the torque wasn't done
 
My 04 Camry front hub to axle torque is 217 ft. lbs. The Double Row Angular Contact bearing outer race is pressed into the spindle and secured with a snap-ring, and the inner race is a light press fit on the hub. The axle splines mate with the hub splines and the nut torque secures the assemble together. The bearing itself is manufactured with close tolerances and doesn't require a pre-load and in fact would be destroyed before turning one revolution. Is that correct?
 
No, it is not correct. Some wheel hubs are made such that the clamp load of the nut puts the force through both inner rings, which butt up to each other. Improper torque will place these inner rings in an improper relative position, resulting in improper clearance that leads to reduced life of the bearing. This is what I meant by referring to stress-strain curves. Metal can get squeezed (change shape) under load.

It is because of the close tolerances in a hub unit that clamp load is critical. The torque is part of the design. It is not as though you are mounting a boss.
 
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